Technical terms about batteries or jargon in battery industry are explained briefly. Please click capital letter buttons of the word.


■All-solid-state batteries

Lithium-ion batteries with solid electrolytes instead of electrolyte solutions (electrolyte solutions are flammable and have safety issues). Solid-state batteries are safer, and facilitate downsizing, capacity expansion, and faster charging. There are great expectations for all-solid-state batteries as the next-generation of lithium-ion batteries, and battery manufacturers are stepping up R&D in this area.

■Auxiliary batteries

Batteries used for starting hybrid electric vehicle systems, power backup for onboard electrical devices, such as car navigation systems, etc.


■Backup batteries

Batteries used to store electricity for use in the event of power outages, disasters, etc.

■Batteries for new automobiles

Batteries supplied by GS Yuasa to automakers for installation in new automobiles.

■Battery modules

Battery modules consist of multiple cells connected together and fixed in place within a single structural frame. Battery modules are often equipped with storage battery management devices to improve safety.

■Blue Energy Co., Ltd.

Established in April 2009 as a joint venture between GS Yuasa and Honda Motor Co., Ltd. Blue Energy manufactures and sells lithium-ion batteries designed for use in hybrid electric vehicles.



Cells are the smallest unit of a battery. They consist of a positive electrode (cathode), a negative electrode (anode), and a separator. Each individual cell can be charged and discharged.

■Cranking performance

The performance of a battery in starting an engine by outputting a large amount of current in a short period of time. Also known as cold cranking amperes (CCA).


■Electric vehicles (EVs)

Vehicles that run on motors powered by batteries that are charged using external electric power sources such as charging stations and household electricity supplies. High energy density is required for electric vehicle batteries as electric vehicles run solely on charged power.

■EN batteries

Batteries that comply with European Norms (EN). EN batteries are lower in height than normal lead-acid batteries, which facilitates the lowering of vehicle bonnet/hood heights and improves vehicle safety. EN batteries generally have specifications suitable for Europe’s colder regions, and using them without alteration in Japan can present high levels of risk. Accordingly, the batteries’ structural design must be optimized for use in Japan. In response to requests from automakers, GS Yuasa develops and supplies EN batteries better suited to Japan’s climactic conditions.
For further details: (in Japanese)

■Energy density

The amount of energy that can be generated by a battery per unit mass or per unit volume of the battery. The units for energy density are Wh/kg and Wh/L.

■Energy storage systems (ESS)

Energy storage systems combine storage batteries (secondary batteries) with power conditioners and are connected to the power grid. The systems store or release power depending on circumstances.


■Feed-in tariff (FIT) schemes

Schemes introduced to popularize the use of renewable energy sources, such as solar power. Feed-in tariff schemes are based on guarantees that electric power companies will purchase electricity generated from renewable energy sources at fixed prices for certain period of times.

■Fuel-cell vehicles (FCVs)

Vehicles that run on motors powered by electricity generated by a chemical reaction between hydrogen and oxygen. Refueling at hydrogen stations is required.


■Hybrid electric vehicles/hybrid vehicles (HEVs)

Vehicles equipped with both gasoline-powered engines and electricity-powered motors. Hybrid electric vehicle batteries require high levels of input and output performance owing to the need for frequent power input and output, such as during regenerative charging when decelerating and discharging when accelerating.


■Internal combustion engine (ICE) vehicles

Vehicles with engines that run on fuels such as gasoline, diesel, etc.


■Lead-acid batteries

Lead-based batteries used for starting vehicle engines, backup electric power, etc. Lead-acid batteries account for approximately 80% of GS Yuasa’s net sales.

■Lithium Energy Japan Ltd.

Established in December 2007 as a joint venture between GS Yuasa, Mitsubishi Corporation, and Mitsubishi Motors Corporation. Lithium Energy Japan manufactures and sells lithium-ion batteries designed for use in plug-in hybrid electric vehicles and electric vehicles.

■Lithium-ion batteries

Batteries in which charging and discharging occurs when lithium ions move between the positive and negative electrodes.

■Lithium iron phosphate (LFP) batteries

A type of iron phosphate-based lithium-ion battery. Lithium iron phosphate batteries have positive electrodes made from lithium iron phosphate.


■Nickel-cobalt-aluminum oxide (NCA) batteries

A type of nickel-based lithium-ion battery. Nickel-cobalt-aluminum oxide batteries have positive electrodes made from a compound of nickel, cobalt, aluminum, etc.

■Nickel-manganese-cobalt oxide (NMC) batteries

A type of lithium-ion battery called ternary lithium batteries. Nickel-manganese-cobalt oxide batteries have positive electrodes made from a compound of nickel, manganese, cobalt, etc.


■Peak cut/Peak shaving

Reduction of electricity usage at times of peak electricity demand.

■Peak shift/Load shifting

Shifting the times when electricity is used away from times of peak electricity demand.

■Plug-in hybrid electric vehicles (PHEVs)

Hybrid electric vehicles that can also be charged using external power sources. Batteries for plug-in hybrid electric vehicles require high energy density to enable long driving ranges.

■Post-FIT residential solar power generation facilities

Residential solar power generation facilities for which the period (from the time of installation) for eligibility for the feed-in tariff (FIT) system has expired.

■Power conditioning systems (PCS)

Systems that convert DC power generated by solar cells, etc. into AC power suitable for use in homes, office buildings, etc.

■Power purchase agreements (PPA)

Power purchase agreements are electricity sales contracts concluded between generators of electricity and consumers.


■Redundant batteries

Batteries used as a backup power source for autonomous driving systems, etc.

■Replacement batteries

Lead-acid batteries used to replace existing batteries during vehicle inspections or to replace spent batteries. GS Yuasa delivers replacement batteries to distributors, auto parts/supplies retailers, auto dealerships, oil wholesalers, etc. Vehicle batteries generally need to be replaced after three to five years. Demand for replacement batteries tends to be seasonal, with the strongest demand in late autumn to early winter.


■Specialized batteries

A general term for batteries used in specialized applications such as spacecraft (satellites, rockets, etc.), aircraft, and submarines.

■Starter batteries

Batteries used to start engines in gasoline-powered vehicles, etc.

■Start & stop vehicles/ ISS (idling stop systems) vehicles

Vehicles that automatically shut down their engines when stopping at traffic lights, etc., then automatically restart their engines when the brake pedal is released. When the engine is shut down the vehicle’s battery continues to power the air conditioning, navigation system, etc. As start & stop vehicle engines are frequently shut down and restarted (discharging a large current each time), the batteries of such vehicles need to be highly durable.
For further details: (in Japanese)


■Traction batteries

Batteries used to power motors in electric vehicles, hybrid electric vehicles, etc.


■Uninterruptible power supplies (UPS)

Uninterruptible power supplies are devices used to supply electricity when electricity is interrupted due to power outages, etc. Uninterruptible power supplies consist of storage batteries and power converters.


■Virtual power plants (VPP)

Systems that use IoT devices to remotely control geographically dispersed energy sources, such as small-scale solar power generation facilities and storage batteries, and make them function like single power plants.


■12V lithium-ion batteries

12V lithium-ion batteries boast high cranking performance and provide an alternative to lead-acid starter batteries. Demand is expected to increase for this type of battery as backup batteries for autonomous vehicles and as an alternative to the lead-acid auxiliary batteries installed in hybrid electric vehicles and electric vehicles.